Cannot edit extended properties

I have added an Extended Property table into my Workflow, but unfortunately I can't seem to edit the table. Here is what I did:

Created a table in the WMX repository (WMX_Capital_Works). The table is owned by the WMX user, and I have granted r/w access to all users in the system (for the moment). The table is NOT versioned. The table has a JOB_ID column

In WMX Administrator I added the Extended property table with the JOB_ID as the link field and with a 1:1 relationship

Then in the Job Type, I selected the Extended properties tab and selected the WMX_Capital_Works table.

I toggled off a few of the fields, (JOB_ID, OBJECTID) and set the parameters for the rest of the fields. Some are editable, some are required, I set alias fields and some default values.

Then I created a job of this job type in the Workflow Manager as my user (adm-gaiseral)

When I toggle the extended properties tab, I can see the fields (displaying the ones that I requested to be visible and astericks beside the one defined as required) but I cannot edit the values.